A single yellow circle with a black outline is drawn at the center of an SVG, forming a simple face. The circle’s radius is set to half the SVG height, with its center positioned using the width and height attributes. Using D3.js v5, the `select` method targets the SVG, and `append` creates the circle, setting its fill and stroke. The example demonstrates basic SVG shape creation and attribute manipulation with D3’s declarative chaining.